In the present study, a new structured lipid with medium- and long-chain triacylglycerols (MLCTs) was synthesized from camellia oil (CO) and Cinnamomum camphora seed oil (CCSO) by enzymatic interesterification. Meanwhile, the antiobesity effects of structured lipid were investigated through observing the changes of enzymes related to lipid mobilization in healthy C57BL/6J mice. Results showed that after synthesis, the major triacylgeride (TAG) species of intesterificated product changed to LaCC/CLaC (12.6 ± 0.46%), LaCO/LCL (21.7 ± 0.76%), CCO/LaCL (14.2 ± 0.55%), COO/OCO (10.8 ± 0.43%), and OOO (18.6 ± 0.64%). Through second-stage molecular distillation, the purity of interesterified product (MLCT) achieved 95.6%. Later, male C57BL/6J mice were applied to study whether the new structured lipid with MLCT has the efficacy of preventing the formation of obesity or not. After feeding with different diets for 6 weeks, MLCTs could reduce body weight and fat deposition in adipose tissue, lower plasma triacylglycerols (TG) (0.89 ± 0.16 mmol/L), plasma total cholesterol (TC) (4.03 ± 0.08 mmol/L), and hepatic lipids (382 ± 34.2 mg/mice) by 28.8%, 16.0%, and 30.5%, respectively, when compared to the control 2 group. This was also accompanied by increasing fecal lipids (113%) and the level of enzymes including cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), hormone-sensitive lipase (HSL), and adipose triglyceride lipase (ATGL) related to lipid mobilization in MLCT group. From the results, it can be concluded that MLCT reduced body fat deposition probably by modulating enzymes related to lipid mobilization in C57BL/6J mice.

Polyglycerol ester is considered an excellent kind of food emulsifier. The aim of the current study was to synthesize polyglycerol fatty acid esters (PGFEs) with different-sized long-chain fatty acids (i.e. long-carbon fatty acid polyglycerol esters, L-PGFEs; medium-carbon fatty acid polyglycerol esters, M-PGFEs; and short-carbon fatty acid polyglycerol esters, S-PGFEs), using Lipozyme 435 as a catalyst in a solvent-free system. Thereafter, the physicochemical properties of the newly synthesized PGFEs and their potential applications as food emulsifiers were investigated. The maximum esterification efficiencies of L-PGFEs, M-PGFEs, and S-PGFEs were 69.37, 67.34, and 71.68%, respectively, at the optimum conditions: a reaction temperature of 84.48 °C, a reaction time of 6 h, a molar ratio of polyglycerol to fatty acid of 1.35:1, and 1.41 wt % enzyme usage (based on the total substrate mass). A high-performance liquid chromatograph equipped with an evaporative light-scattering detector (HPLC-ELSD) and an electrospray-ionization mass spectrometer (ESI-MS) were employed to identify the synthesized products. The results demonstrated that the main components of these PGFEs were dimeric glycerides (68.3%), triglycerides (13.13%), and a small amount of tetraglycerides (3.18%). The properties of the PGFEs were characterized by physical and chemical methods. Compared with M-PGFEs and S-PGFEs, L-PGFEs had the best physicochemical properties without any obvious odor. Further, the emulsion capabilities of these different long-chain PGFEs were evaluated via examining the particle sizes and storage stabilities and comparing them with those of glycerin monostearate (GMS). The results showed that the emulsions prepared with L-PGFEs had the best stability and the smallest particle sizes (16.8 nm) compared with those of M-PGFEs, S-PGFEs, and GMS, and they were not prone to oil-droplet coalescence or the separation of oil and water. From the current study, the newly synthesized PGFEs with long-chain fatty acids showed the best advantages as a food emulsifier compared with M-PGFEs, S-PGFEs, and even glycerin monostearate.